Cable tray systems are used to support, fasten, and manage lengths of cables, tubes, pipe, conduits, and wires. Cable tray systems may be used in commercial and industrial facilities, power generation facilities, manufacturing plants, and the like. Cable tray systems may include components such as cable trays, connector pieces, and brackets, which are secured to one another by fasteners (e.g., bolts, nuts, or other fasteners). The cable trays used in these systems often have a U-shaped or L-shaped cross-section, with the cables, tubes, pipe, conduits, and/or wires being carried within the U-shape or L-shape and being fixed to or guided within the cable trays.
In some applications, the primary requirement for a completed cable tray system is structural rigidity. For other applications, the completed system is preferably devised to minimize or eliminate electrical arcing between connected members of the system by maintaining conductive continuity in the event that the system becomes electrically energized.
Cable tray systems typically are constructed of linear runs of trays connected together to span the required length of a given application. Separate sections of trays are fastened together to achieve the requisite length. Some applications may allow an entire cable tray run to be installed in a straight line without interruption. Often, previously installed features, such as pipes, conduits, ductwork, or even other cable tray runs, are obstacles to the installation of a linear cable tray run, requiring the new cable tray run to be horizontally redirected from its original path. In some circumstances, it may be desirable to redirect the path of a cable tray from one direction to another within a single horizontal plane, perhaps multiple times along its length, to accommodate the requirements of the particular application.
The extent to which the course of a cable tray run must be redirected may vary widely, depending on the individual site. Often, the degree of redirection that may be necessary is difficult to predict at the beginning of the installation process without extensive and, in view of the present invention, unnecessary planning, making it equally difficult to arrive on-site with sufficient hardware to complete the installation. Accordingly, it would be advantageous to have connectors that permit the adjustable redirection of a cable tray run, rather than connectors with fixed geometry or that require custom fitting or fabrication on-site.
A first method of redirecting a cable tray run has been to use rigid, non-adjustable interconnectors of fixed angle of redirection (e.g., 30°, 45°, 60° 90°, etc.) in the run, to avoid obstructing interferences or to change direction as otherwise required. Prior devices used to achieve that result are shown in FIGS. 1 and 2. Specifically, use of device 10 depicted in FIG. 1 provides for ninety degrees (90°) of course redirection to a cable tray run. In use, a first section of cable tray (not shown) may be fastened to a first cable tray attachment zone 11 of device 10, fitting connecting bolts (not shown) through holes 12a-c. A second section of cable tray (not shown) may be fastened to cable tray attachment zone 15 of device 10, fitting additional connecting bolts (not shown) through holes 16a-c. So interconnected, device 10 provides only a rigid, non-adjustable 90° angle of redirection to a cable tray run.
Similarly, use of device 20 depicted in FIG. 2 provides for a 45° angle of course redirection to a cable tray run. A first section of cable tray (not shown) may be fastened to a first cable tray attachment zone 21 of device 20, fitting connecting bolts (not shown) through holes 22a-c. A second section of cable tray (not shown) may be fastened to a second cable tray attachment zone 25 of device 20, fitting additional connecting bolts (not shown) through holes 26a-b. So interconnected, device 20 provides only a rigid, non-adjustable 45° angle of redirection to a cable tray run.
Clearly, however, use of either device 10 or device 20 would provide only two choices of cable tray course redirection—either 45° or 90°—and would offer no adjustability of the redirection to fit site-specific requirements.
Another method of accomplishing such redirection has been to require the installer to cut, fit, and attach custom-fabricated members in the field to work around an obstacle. Such work has been suffered as labor intensive, time consuming, costly, and undesirable. In addition, such an approach does not provide for adjustability of the redirection of the cable trays.
Another method of redirecting a cable tray run may be found in U.S. Pat. No. 4,232,845, which is directed toward a modular support system constructed from a plurality of transportable modular components for assembly into shelves, platforms, ladders, walkways, and other similar structures. The disclosed apparatus provides for redirection of a cable track course. However, the apparatus accomplishes such redirection through the use of non-adjustable members, such as component 222. No adjustability between connected sections of a cable track, and therefore no adjustable range of angular relationships within a run of cable track, may be accomplished.
Yet another method of redirecting a cable tray run may be found in U.S. Pat. No. 3,137,468. While such an apparatus may result in a cable track with sections redirected, such redirection is accomplished by use of a form section of cable track. No provision is made for adjustability between connected sections of a cable track and, therefore, no range of angular relationships within a run of cable track can be accomplished.
U.S. Pat. No. 4,432,519 may describe a cable mounting ladder for installation to a building or other structure constructed so that curved sections can be interconnected to avoid obstructions. The apparatus may accomplish such avoidance only with the use of pre-fabricated, fixed geometry, angled interconnectors between adjacent tray members, resulting in a labor-intensive, cumbersome system. Furthermore, such a device provides no adjustability between interconnected sections of cable track.
Finally, U.S. Pat. No. 6,498,296 may describe a cable track system to allow for redirection of the cable tray course. Accomplishing such redirection with this patented system, though, requires the use of rigid, pre-fabricated joining members, and, therefore, suffers the same disadvantages as described above, including the absence of any opportunity to adjust the angle between interconnected sections of cable track.